Multiple grinder



Oct. 11, 1932. c, T. RAULE MULTIPLE GRINDER 3 Sheets-Sheet 1 Original Filed Sept.2l, 1926 Oct. 11, 1932. c. T. RAULE 1,882,447

MULTIPLE GRINDER Original Filed Sept. 21, 1926 5 Sheets-Sheet 2 Patented Oct. 11, 1932 I i E TATES PATENT OFFICE- cmrronnr. RAULE; or BROOKLINEPENNSYLVANIA MULTIPLE GRINDER Orl'ginalapplication filed September 21, 1926, Serial 170. 136,771. Divided and this application filed July 31,

1930. Serial No. 471,936.

multiple external grinder, Serial No. 136,771

filed September 21, 1926.

A; purpose of my invention is to obtain quantity production of precision external ground duplicate parts Whether the ground surfaces are to be straight, tapered or curved. A' further purpose'isto load or unload a multiple external grinder automatically.

Avfurther purpose is to actuate loading and runloadin grinder at the same points respectively in the .pathcf the travel of a plurality of bodily movable work-holders. cooperating with the same Wheel, preferably using a gravity feed. A further purpose is to apply an automatic gravity feed to a multiple external grinder.

Further purposes will appear in the specification and in the claims.

I prefer to illustrate my invention by one form only'of'the many in which it may be carried out, selecting aform for its illustra-' tivevalue inorder to disclose to best advantage the principles of my invention.

Allof thefigures are viewed by me as diagrammatic to the extent at least that I have selected the simple outlines of parts.

capable of carrying out the functions describedyratherthan more complex and finished: illustrations such as would represent the best designs for accomplishing the results.

Figure 1 is a fragmentary plan view of one form of my invention. v

F igure2zis a fragmentary section taken upon-line 2'2-of Figure 1.

Figure 3 is afragmentary side elevation of parttof'the structure shown in Figures 1 and 2.

Figure 4 is a diagrammatic View to illustratethe relative positions of certain parts throughout the cycle of operations.

mechanisms of an external Figure 5 is an enlarged section taken upon the line 55 of Fi ure l and illustrating one work-holding and drivingmechanism.

In the drawings like numerals refer to like parts.

Describing in illustration and not in limitation and referring to the drawings In Figures 1 3 I show a stationary frame 16 upon which is formed with acentral verti cal bearing 17 shouldered at 18 to receive the hub 19 of a rotatable table 20'upon'which table the Work is carried in work-holders.

At any convenient point in or upon the frame I mount a motor 21 connected by belt 22 with pulley 23upon a shaft 24 shown as supported in bearings 25 and 26. vThe shaft carries a gear 27 which engages with an internal gear 28 rigid with the table to rotate the-table.

A gear 29 upon the shaft 24 engages} with gear 30-up0n a shaft 31 having hearing within the bearing 17 to rotate the shaft and With-it to rotate the grinding wheel 31" mounted upon the top of the shaft. This grinding wheel cooperates withall of the work-holders arranged about the table and may operate upon all of the pieces of work therein at the same time, except those at positions of charg ing and discharging.

In order to protect against grinding too' much at the same part of the wheel width'thewheel is traversed (reciprocated) axially while it is continuously rotated. This trav ersing is secured by spiral gearing 32'con-' necting the shaft 24 with a shaft 33; a worm 36lwith the bottom 38 of the'shaft 31. The gear 30 is given suflicient length of toothto continue in engagement with gear 29 at all times notwithstanding the traversing.

The table 20 is provided at intervals about 1 its circumference with a plurality-of bearings 39 within which are supported shafts 40, carrying the gears 41 and 42 respectively above and below the bearings. This construction is shown enlarged in Figure 5.

Gears 41 and 42 are rigidly mounted upon the shaft 40, a key 41 for gear 41 being shown in Figure 5. The gear 43 is coaxial with the turntable and fastened in any suitable way to the stationary supporting StTllC. ture.

The shaft 40 is extended above the gear 41 to form bearing 44 for the hub 45 of a center chuck which is shown in Figures 2 and 3 held down by. gravity only but in Figure 5 as held down upon the shaft by washers 46 and nuts 47. I

The sleeve 45 forms a hub for arms 48 and 49 which carry coaxial centers 50 and 51, the upper center 50 being a dead center and the lower center 51 being optionally either liVe as in Figure 5 or dead as in Figure 6 of the parent case.

The dead center 50 is spring-pressed downwardly by a spring 52 within a recess 53 where it is centered by a flange 54. This shaft 55 extends through the arm to ahead 56.

The live center shaft 57 of Figure 5 has its bearing in the arm 49, resting upon a flange 58 and carrying at its lower end a gear 59 meshing with gear 41. The work 60 is driven .by any suitable means such as a pin 61 from the flange 58 extending into a groove 62 of the work.

By this construction the rotation of the table carries the shaft 40 bodily about the axis of the table while rotating the gear 42 upon its own axis. The gear 42 is mounted upon the same shaftas, and therefore car- 7, ries the gear. 41 which in turn rotates the 'work'by rotating the flange 58 carrying the pin 61.

The center chuck is free to swing about the extension 44 of the shaft 40, permitting the'work to be swung toward or away from the grinding wheel as desired.

Recurring to Figures 1, 2 and 3; at any suitable point at a distance from the shaft extension 44, the arm 49 is provided with a radial or side extension 66 whose terminal 67 engages the inner surface 68 of a feed cam 69su'rround1ng all or the major portion of the path or orbit of movement travelled by the work-holders and work and this cam may tend to throw the wheel 59 outwardly from the center of the wheel, maintaining the ter minal 67 in engagement with the cam For additional assurance of this tendency of the work to move outwardly toward the cam I show a tension spring 70 pulling upon the arm at the opposite side, of the center of shaft '40 with respect to the work.

The terminal 67 is shown as capable of adjustment by threading into the extension 66 as at 71 by nuts 72.

The cam .69 is shown conventionally as supported from a frame rim 73 by studs 74 which. pass through the rim and are adjustably held in place by nuts 75 and 76. The studs are rigidly fastened to the rim and thread through the cam. The cam is shown as sectioned at 77 at a point beyond .thatat which grinding is completed to permit the slight variation of length incident to adjustments in the radial position of thecam and to permit making it up in several parts.

In practice the cam need not extend all thebe an ordinary The rotor member is mounted upon a shaft; 80 that 1s driven through splral gears 81,.

shaft 82 and spiral gears 83, one of which is mounted on the shaft 24. r

A semicircular gauge 85 below the circular path of the clamps 79 is used to exactly register the work pieces vertically in the clamps. The work pieces are put into the rotating clamps by hand and exactly positioned vertically by pushing down to the gauge 85.

The travel of the feed clamps is synchronized with that of the work-holders upon the turn-table, successive work pieces being presented by the successive clamps to position between the centers 50 and 51 in the successive work-holders as these centers successively reach the loading position.

When this position is reached the axis of the work piece in the clamp lies 'momen-.

tarily in line with the common axis of'the upper and I having been raised some time before by rea son of the'bottom of the flange 56 riding along the upper surface of the cam 86. The work piece is at a higher level than is the dead center.

At charging position the flange 56 comes-to an abrupt drop 87 on the cam 86 and as a result the upper center .50 springs downwardly under the action of the spring 52, the point of the center entering the centering recess 88 in the top of the work piece 60 and pushing the work piece downwardly outof the clamp and into centering engagement with the lower center 51.

As the work progresses along the cycle of operations from the point of loading it is 111- 1' lower centers, theupper centerwardly pressed against the grinding wheel at the same time that it is rotated and is carried bodily about the axis of the wheel. The inward feed depends upon the setting of cam and the setting of the terminals 67; both of which are preliminarily designed to suit the work and are capable of adjustment.

The cycle of operations is shown diagrammatically in the hypothetical curves A, B and C- of Figure 4.

In these curves the abscissae represent the angular or circumferential position around the machine or, putting it differently, represent successive positions along the common circumferential orbit of the work pieces. The abscissa of any point of any of these curves corresponds to a definite angular position about the axis of the machine. The ordinates in curve A represent the distances of the inner surface of the feed cam from the outer surface of the grinding wheel, and the ordinates of the curves B and C represent, respectively the elevation of. the work piece 60 and the elevation of the upper dead center 50. v

The cycle of operations is illustrated upon a single unit and takes place upon successive Work pieces during successive circuits of the machine at each work-holding unit.

At the line 89 the work piece 60, which has just been positioned between the centers and 51 by one of the feed clamps, is engaged by the released dead center 50. The flange or head 56 upon the top of the stem of the dead center has been riding along the cam track 86 to hold the dead center in raised position. At the line 89 of the curves B and U the cam head reaches the abrupt drop 87, Figure 2, in the cam and the spring 52 forces the center downward into the center of the work piece and drives the work piece downwardly from between the clamping jaws 79 on to the lower center 51.

The work piece is shown with an offset longitudinally directed projection by which driving is effected. Here its function is performed by a wall of a diametral groove 62. The pin 61 in the upper side of the revolving flange 58 in rotating about the axis of the shaft 57, quickly finds the groove, after which the work rotates with the driving member 58.

The feed cam is, at this time, relatively far from the grinding surface of the wheel so that the work piece is positioned well away from the wheel. Between the lines 90 and 91 the feed cam is formed to bring the work rapidly toward the wheel.

There is some variation in the initial sizes of the work pieces, and therefore some vari the work piece and the wheel will be variant with the different work pieces accordinggto by the time the line 94 is reached. At'the line 95, which is somewhat after the completion of the feeding operation the work-hold er brings the work pieceinto a guideway 96' (Figure 1) which is forked at its end 97 to pass the center 51 and pin '61 (Figure V The bottom of the work piece is engaged by the upwardly sloping guideway upon op posite sides near its outer circumference. As the table rotates the work piece is forced to slide up the forked guideway, which lifts the work piece to clear the lower center 51 and the drive pin 61. During the liftinggof the work piece by the forked guideway the dead center 50 lifts against the action of the spring 52. The lifting of the work piece is complete at the line 98 where the upward slope of the forked guideway ends.

At-some line 99,: which is desirably substantially coincident with the line 98, the: bottom of the head or flange 56 upon the top of the stem 55, carrying the dead center, engages the upper surface of an upwardly sloping portion 100 of the cam 86 Between the lines 99 and 101-the head rides up the inclined surface of this cam, raising the'upperr center from its engagement with. the Work piece and thus leaving the work piece in the guideway 96 along which it is pushed bysucceeding Work pieces.

At the line 102, which is coincident with the line 90, the cycle begins again, a new work piece being inserted into proper position between the upper and lower centers and the upper center snapping down under the ac tion of the spring as the head reaches the drop 87 of the cam 86. v

In view of my invention and disclosure variations and modifications to meet individual whim or particular need will doubtless become evident to others skilled in the art, to obtain all or part of the benefits of my invention without copying the structure shown, and I, therefore, claim all such in so far as they fall within the reasonable spirit and scope of my invention.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is: l

1. In an external grinder, a grinding wheel, centered chucks spaced along an adjustable common orbit around the wheel, means for supporting and moving the chucks along the orbit and other means for successively closing the chucks at a loading point of the orbit and for successively opening the chucks at a portion of the orbit subsequent to the grinding and before the loading point,

in combination with a rotary loading device adapted to loosely hold a work piece and carry it into position to be taken hold of by an open chuck at the loading position and mechanism synchronizing the rotation ofthe loading device to bring it successively into registry with the axes of the successive chucks at the loading position of the orbit.

2. In an external grinder, a grinding wheel, centered chucks spaced along an adjustable common orbit about the wheel,

means for supporting and moving the chucks along the orbit and other means for successlvely closing the chucks at a loading pomt of the orbit and for successively opening the chucks at a portion of the orbit subsequent to the grinding and before the loading point, in combination with a rotary loading device adapted to loosely hold a Work piece and carry it into position to be taken hold of by the chuck at the leading position and mechanism synchronizing the rotation of the loading device to bring it successively into registry with the axes of the successive chucks at the loading position of the orbit, and the said loading device including a rotor member having angularly spaced radial arms and outwardly directed spring clamps at the end thereof. v

'8. Mechanism in accord with claim 1 characterized by the central chucks each including a lower driven member and an upper member spring pressed toward the lower member and coaxial therewith, the said means for supporting and moving the chucks along the orbit including a cam surrounding the orbit and positioning the chucks away from the wheel a discharge portion of the orbit, and a bifurcated discharge trough adapted to engage the bottom of a work piece carried by a chuck, to guide the work piece upwardly out of engagement with the said lower member along the trough with a corresponding upward and opening movement of the upper member, the lower member passing onward through the bifurcation and a second cam holding the raised upper member 1n open position to the loading point.

CLIFFORD T. RAULE. 

